Neoalloionema indicum n. sp. (Nematoda: Alloionematidae), a new alloionematid from India

Abstract

A new nematode species belonging to the family Alloionematidae was originally isolated by Dr Marie Anne Félix on 16 December 2007 from a rotting coconut at the boat boarding point in Estuary island resort, Poovar, Kerala, India. Both morphologically and molecularly, the new isolate resembles Neoalloionema tricaudatum but, unlike N. tricaudatum this species has no phasmidial ‘horns’ in the juvenile stage, even though prominent structures in the mid-tail of dauer juveniles were observed. Females are characterised by a body length of 947 (869-1030) μm, vulva in the mid-body region, long, and tapering tail with a minute post-anal swelling. Males are 678 (606-757) μm long with a long tapering tail that is very thick at base. They are further characterised by seven pairs of genital papillae and a single genital papilla. Dauer juveniles are only 391 (364-434) μm long, thin and almost straight when heat-killed. Large, prominent phasmids are located laterally at the mid-tail region and lateral fields consisting of a single ridge are present. Several morphological and molecular differences encouraged us to describe the nematode as N. indicum n. sp. The ecology of the newly described species is unknown, but it is probably a saprophytic bacteriophagous nematode preferring rotting organic material.